dho

For the most performance gain for the buck, I'd recommend a DPR Stage VI head first. Read up on the build at SE-R.net. "The engine made 164.1 hp@ 6300 rpm and 151.8 ft/lb of torque@ 4500 rpm at the wheels on DRR's Dynojet chassis dyno. This equates to almost 190 crank hp." Ask Dan@DPR to make it for the most amount of HP/TQ NA'd for the street (to pass emissions). You can send him your intake manifold for porting at the same time as the head.

Stage VI $1200 W/ Manifold
Stage VI $1500 Full welding and combustion chamber modifications (raise compression by .5)
Stage VI $2300 - added valves and coating etc

Then after you do the head/intake manifold, get the bolt-ons. You can make a custom cat-back exhaust with mandrel bends from www.summitracing.com www.jegs.com and www.jcwhitney.com You'll need two 90 degree bends and two long-radius 45 degree bends. (@ jegs you can get U-bends for $15) Get a thrush 22" glasspack @ summitracing $16 as a resonator. Then get a dynomax ultra-flow muffler $59. Total cost for parts: $110 + shipping Once you get all the parts, go to a muffler shop and have them TIG weld 'em together and put it on your car... they'll charge between $40-120 for labor. Another thing that will help you out is a random technology high flow cat $180 (bolt-on). So total cost for the cat & back exhaust about $400. Go to my website to hear a similar setup on my 1.6 sentra.

__________________
Dan
1992 Nissan SE-R
2001 MR2 Spyder

 

shoe

check the MAF ground, TPS adjustment, O2 sensor connection, base ignition timing...i set my timing at 21 degrees and use 92 octane gas.

shoe

Your not gonna gain 50 HP with only a port and polish, that test was done with a shit load of other aftermarket products. I think Mike Kojima said he gained somewhere in the range of 10 HP with the ported head.

i also have a NX2K and what i did was advnace the timing, adjust the TPS a little past 4 volts at WOT, increase the spark plug gap, rotate the MAF and a few other things and my quickest time was 15.4 at 90 MPH. Thats with no aftermarket mods.

my opinion on aftermarket mods, i would recommend you getting basic mods to get your engine breathing easier. a custom cold air intake and exhaust using the same method as "DHO". If you have your own welder, even better. Then a Pacesetter, Hotshot, or AEBS header. Then cams would be nice. If you want streetable cams you would want cams with duration in the range of 260-270 degrees, anything higher, you will have a lopey idle. If you have a good mechanical apptitude, there are a few things you can do which wont cost very much. You can do your own porting job with a carbide and sand paper catridge roll. The idea is to smooth the ports rather than enlarging it. Smoothing the valve seat to the throat area will increase flow significantly also. after you do your port and polish, a machine shop charges approx $200-250 to do a 3 angle valve job. You may also have the cylinder head milled approx .030 inches which will give you a 10-1 compression ratio, however you will need cam sprockets to properly adjust the cam timing back.

dho

I'm not really sure what the exact HP gains would be if you made the head for all out performance. shoe, you probably know a million times more than I do but all the information that I know, I've read/heard/watched from other people & sources. Nissan had a 300bhp SR20! You could probably make an all out GA16 to do 200bhp! DPR's heads are not just port & polished, there' not just 3 angle valve jobs, their full racing heads. They offer 5 angle valve jobs and everything else. They could port the head massively for the most amount of HP/TQ, do lightened valves, valvesprings, retainers, they can modify the head for the cams you purchase, they can raise the compression, they can modify the combustion chamber with the clover-leaf-pent design used in Corvette's, they can coat parts of the head, they can do a lot of stuff to it, just depends on what you're wanting to do. I bet he could raise the compression to 11:1 or more in the head. From what I've read, the head design makes up 90% of the total motor horsepower. If the head isn't made right you could have a lot less power than you began with.

Check some of the archives at DPR's website to see some of their work and dyno's. Here's a link to their Services.

__________________
Dan
1992 Nissan SE-R
2001 MR2 Spyder

dho

Here's three pictures of my custom CAI. You can find some others at my website: http://1minute.com/dan/

__________________
Dan
1992 Nissan SE-R
2001 MR2 Spyder

Zak91SE-R

IMO, it's not worth the money. You will not get anywhere near 50 HP with just headwork. You'll be lucky to break 200 at the wheels, and that's if you also have all the bolt-ons and I'm being optimistic to the point of fantasy here. Considering you'll have to spend say $2500 to get even that much HP (or very likely less than that), it doesn't make very much sense when you can get an SR20DET for quite a bit less money than that and make more HP right off the bat.

I mean the DETs start at 205 or 230 HP depending on which one you get, and then they just make more from that point on. Also, the DET runs like a stock motor. A built NA motor making 200 whp won't run anything like stock. And then of course you can turn up the boost on a turbo motor if you want more power.

If you want more than 200 HP, going NA with an SE-R really doesn't make much sense to me, not considering how well the SR20 engine takes to turbocharging, and all the options there are out there.

Crono1321

Very good poin Zak. The problem however with some of us is that we are afraid to take the "plunge" into the vast "turbo pool." I know it is a lot easier for me to go out and piece together an all-motor monster, but I dread the thought of installing a turbo or swapping a different engine into the car. I don't want to speak for everyone, but I know that from experience, my friend has an Integra LS and bought a type-R head to swap. It turned out after months of it sitting in his garage, he sold it because the project was too big to handle, and too many things were going wrong. Sold the engine for twice what he paid, and now has a fast N/A car.

Ju§tin

dho

Zak I can understand where you are coming from. On the other hand I have a GA16DE. If you had basically a new motor, tranny, converter, motormounts, wires, plugs, wire amplifier, custom CAI, cat& back exhaust, auto transmission parts, and you were still paying on it, why would you swap out the motor and tranny and void the 5yr warranty on the engine? If I build up for NA, I don't go backwards into more debt to try to sell all the 1.6 parts. In addition to that, if a SR20DET was installed like I planned back in September, who would be willing to change the transmission from Automatic to a manual and find all of the little parts that are necessary for that swap? Also, what about street legality? How do you know if these SR20DET's weren't stolen or sold in the black market?

Since jayrok has a NX2000 it's a 2.0 right? Well he can do either of the two options (NA or Turbo). It depends on his HP/TQ goals and his budget. Also, he has to decide if it's going to be street legal or not. If he was going turbo, why doesn't he just get a turbo & manifold and other parts of the SR20DET and install them on his motor and when he's ready he could upgrade the internals. This would be less expensive than getting a full SR20DET. Since he has a 2.0, why buy another motor with just 20,000 less miles for around $2,000? He could get all the parts for under $1000 maybe even up to $1500 for the turbo & stuff. Hotshot has a BB install kit which consists of a FMIC and a 3" downpipe for $1100. All jayrok would have to do is find a turbo manifold, the turbo, blow off valve, and maybe some gauges.

I personally would go for NA anyday for reliability unless I could afford a good quality SR20DET installed with everything done to it! Let's get realistic, some people are on budgets. My price for a SR20DET swap into a 1.6L auto sentra was about $8,000. $2000 motor, $1100 HS install kit (FMIC & 3" DP), $1500 labor for tranny swap, $1200 tranny and parts (Ecu), $1000 motor install, $600 exhaust, and $500-600 for gauges and boost controller and turbo timer.

__________________
Dan
1992 Nissan SE-R
2001 MR2 Spyder

shoe

i had a turbo ready to install a couple months ago but i sold it to go N/A. My first car was a FC3S RX7 turbo 2 and ran 13.98 at 103 MPH with basic mods. Turbo's are definately the way to go if you want massive power but i wanted to take on the N/A challenge. The main reason why is because 2 of my friends have 240SX's with SR20DET's. One of them pretty much has a stock set up with exhaust and intake and i can keep up with him on the freeway and my other friend has a front mount, exhaust, etc and only slightly pulls from me on the top end. Both are running stock boost. I know for a fact that it wont take much to spank them going N/A, so thats why i sold the turbo.

dho

You know that the those 240's will only do mid 15's to high 14's with the SR20DET's stock depending on the driver. I think there's a weight difference of 600-800lbs between them and the sentra's. Atleast you're be able to beat 80% of those riced up civics! The only honda's i'm worried about are the Greddy Turbo'd Civic SI and a Greddy Turbo'd Prelude. Power to the NA! Let's see some 14 second NA GA16DE's and some 13 second NA SR20DE's!

__________________
Dan
1992 Nissan SE-R
2001 MR2 Spyder

Zak91SE-R

I can see where y'all are coming from, but consider this: I had an NX2000 with an SR20DET. It was a Bluebird DET making 205 HP stock. I added a FMIC, and a 3" exhaust system. It did a 13.8 @ 101 MPH, and here's the kicker boys and girls: it was completely stock. That's right, it was at 6.5 psi with the smaller t25 turbo. So not only was it that quick, but it was stock in every sense of the word. It drove like stock, was reliable like stock and it installed like stock too.

Now how much money is it going to take to run a 13.8 @ 101 MPH NA? I guarantee you it will cost you more than what it costs to get a BB DET, and in addition to that your car will have a very lumpy idle and it won't make much power under 5000 RPM. It'll also have worse gas mileage than a DET in addition to being generally rougher and having a crapload of aftermarket parts on it.

And all of that is in addition to making less power than even the stockest of stock DETs. And if reliability is a factor at all, a DET will serve you better in that regard. think about it - a DET is a factory stock motor. It goes through the same rigorous stress testing all the other engines go through. Combine that with the fact that you can very literally simply turn the boost up to 10 or 11 psi and gain maybe 30-40 wheel HP over stock (which is already 205 crank) while still retaining reliability, and daily driveability, and well... then you're running more like mid 13s with an engine that feels, sounds and drives like stock.

That's pretty hard to beat by anybody's measure. Now if you want to go NA just because you really want to, then more power to you. Just be aware that you can achieve speed far easier and for less money with a turbo system or a full DET.

oh, and Dan - 240SXs are maybe 300 lbs. more than Sentras, and I saw a GReddy turbo Civic at the drag strip once - he ran a 15.1.